Loud noises can be overwhelming and distressing for many autistic children. Autism is a neurodevelopmental disorder characterized by challenges with social communication and interaction, as well as restricted and repetitive behaviors. Many autistic individuals have sensory processing differences that make them sensitive to sights, sounds, smells, textures, and tastes. Loud noises in particular can be very bothersome for autistic children due to hypersensitivity in hearing. Understanding why loud noises are difficult for autistic children can help parents and caregivers make accommodations to help reduce noise sensitivities.
What is hyperacusis?
Hyperacusis is a condition characterized by an increased sensitivity to certain frequencies and volume ranges of sound. Individuals with hyperacusis have a lowered tolerance for everyday sounds that most people find tolerable. Sounds that are typically not bothersome or ignored by others can be extremely loud, frightening, and painful for those with hyperacusis. The most common sounds that bother individuals with hyperacusis are things like noise from restaurants or traffic, machinery, animals, crowds, slamming doors, sirens, vacuums, lawn mowers, and other environmental noises. Hyperacusis makes it challenging for autistic children to filter out unwanted noise from their surroundings.
Prevalence
Hyperacusis is highly prevalent among autistic individuals. Studies show that anywhere from 55-88% of autistic children experience some degree of hyperacusis compared to only 2-15% of neurotypical children. The wide range in prevalence is likely due to differences in how hyperacusis is defined and measured across studies. Nevertheless, these statistics demonstrate that hyperacusis is very common in autism and far more prevalent than in the general population.
Overwhelming and painful
For autistic children with hyperacusis, loud sounds can be physically painful and cause great distress. Noises that most people find tolerable are processed at amplified volumes by their brain. Even moderate sounds like the radio, telephone, or a dog barking can be processed as extremely jarring. The noise overload can cause autistic children to cover their ears, cry, have meltdowns, or try to escape the unpleasant sound. What may seem like minor background noise to others is overwhelming and unbearable for autistic kids with auditory sensitivities.
Enhanced sound perception
Research suggests autistic individuals may have enhanced sound perception compared to non-autistic people. They are able to detect smaller differences in auditory stimuli and have decreased sound detection thresholds. This means they can hear lower volumes and smaller changes in pitch that others cannot detect. Their brains are hyperaware of the auditory environment.
While enhanced auditory perception can be a strength in some ways, it underlies the hypersensitivities associated with autism spectrum disorder. Even faint or distant noises can be distressing. Background sounds most people naturally tune out are very noticeable. There is too much auditory input for their brains to process, so even moderate volumes are overwhelming. Enhanced sound perception helps explain why autistic children struggle to filter out excess noise.
Differences in auditory cortex
Studies using electroencephalography (EEG) and magnetic resonance imaging (MRI) have identified functional and structural differences in the auditory cortex of autistic individuals that may account for hyperacusis. The auditory cortex located in the temporal lobe of the brain processes incoming auditory information.
Research has found the auditory cortex of autistic children shows enhanced activation in response to mildly unpleasant noises. Other findings show reduced neural adaptation to repeated sounds. These abnormalities suggest their auditory cortex does not adjust to noise in the typical way. There is heightened sensitivity that persists rather than adapting and tuning down stimulation. Differences in gray matter volume in areas of the auditory cortex have also been noted. Taken together, atypical auditory cortex functioning and structure appear to underpin noise sensitivities in autism spectrum disorder.
Emotional response to sounds
In addition to amplified noise perception, autistic children may have strong emotional and behavioral reactions to sounds considered normal or neutral by others. Things like a clock ticking, dripping faucet, or hum of an appliance can provoke intense distress or agitation. Even pleasant sounds like music or singing can be irritating.
Research indicates autistic children have atypical emotional processing of auditory stimuli. Parts of the brain that regulate emotional response are more reactive to sound. When they hear sudden loud noises, voices, or other unexpected sounds, it triggers a heightened emotional reaction and release of stress hormones. There is an emotional overload and loss of emotional control.
Other studies show autistic children have greater connectivity between brain regions responsible for processing emotions and sensory stimuli. This could explain their strong behavioral reactions to sounds. Loud noises that make them emotionally dysregulated lead to covering ears, crying, or outbursts. Sounds are not just louder, but intensely disturbing.
Misophonia
Some autistic children may experience a condition called misophonia in which specific sounds provoke anger, anxiety, disgust, or distress. These trigger sounds are often produced by another person, such as chewing, coughing, tapping, or pen clicking. Misophonia and hyperacusis appear to be related but distinct conditions that can co-occur in autistic children and make sounds intensely upsetting.
How parents can help
There are various ways parents can help autistic children cope with auditory sensitivities:
Provide noise-cancelling headphones
Noise-cancelling headphones that cover the entire ear can be very useful for blocking out unwanted sounds. Allowing autistic kids to wear headphones helps give them more control over their auditory environment. It reduces overwhelming noise input. Look for child-sizes adjustable headphones that ensure proper fit.
Use earplugs or earmuffs
Earplugs made from silicone or foam are an affordable option to help shut out noise for autistic kids. Earmuffs that cover the entire outer ear, similar to headphones but without playing music, are another product to consider. Carry a supply of earplugs or earmuffs in your child’s backpack or with you when out and about.
Create a quiet space at home
Set up a designated quiet room or area in your home where your child can go to get away from noise overstimulation. Install thick curtains, rugs, and soft furnishings to absorb sound. Make it a comfortable space for your child to relax and unwind in a quieter setting. Provide noise-cancelling headphones or other accessories in this space.
Give warnings about loud noise
If you know your child will be exposed to a loud noise like a fire drill at school or thunderstorm, give them advance warning so they can use strategies to cope. Prepare them for noisy environments like birthday parties or restaurants so they aren’t caught off guard.
Model calming techniques
Teach your child techniques to stay calm when overwhelmed by loud noises. Breathing exercises, meditation, and positive self-talk can help counteract the stress response. Model these coping strategies yourself. For younger kids use social stories and visual aids.
Identify triggers
Pay attention to sounds that most frequently upset your child like vacuum cleaners, hand dryers, or car horns. Think about ways to minimize exposure to these noise triggers or provide safer alternatives. For example, give your child noise-cancelling headphones to wear when vacuuming.
Use apps to measure sound
Apps like SoundPrint and dbraIn allow you to measure the decibel level of sounds. Checking noise levels can help you better understand your child’s sensory environment and make adjustments. It also helps validate their experiences.
Work with your child’s school
Set up accommodations with your child’s school like noise-cancelling headphones for assemblies or fire drills. See if your child can go to a quiet room if overwhelmed. Educate teachers about supporting children with auditory sensitivities.
See an occupational therapist
Occupational therapists can assess your child’s sensory sensitivities and recommend strategies to help process sounds and cope with hyperacusis. Visiting an audiologist may also be beneficial. Getting professional support ensures you address noise sensitivities effectively.
Conclusion
Loud noises can be extremely distressing for autistic children due to hyperacusis, enhanced sound perception, and atypical emotional sound processing. However, there are many ways parents can help reduce noise sensitivities. Accommodating auditory needs, avoiding triggers, and teaching calming techniques all help autistic kids manage hyperacusis. With proper support, they can thrive despite noise sensitivities. Understanding why loud noise is challenging helps create an environment tailored to their sensory needs.
